Suture anchors and assemblies for attaching soft tissue to bone

ABSTRACT

Improved bone anchors are disclosed for anchoring one or more sutures attached to soft tissue to a bone. The bone anchor has an anchor body that extends between a distal and a proximal end. A bore is formed axially in the anchor body and opens at the proximal end. One or more pins are fixed within the bore of the anchor body. One or more sutures can be looped on the pins for anchoring soft tissue to bone. The anchor body has a socket within the bore for receiving a driver tool. The distal end of the anchor body forms a non-threaded extension, which stabilizes the bone anchor, and helps prevent lateral movement during use. In one embodiment, the anchor body has coarse threads for engaging soft bone tissue and fine threads for engaging hard bone tissue.

RELATED APPLICATION Related Application

This application is a continuation of U.S. patent application Ser. No.13/297,913, filed Nov. 16, 2011, entitled “BONE ANCHORS FOR USE INATTACHING SOFT TISSUE TO BONE,” which is a division of U.S. patentapplication Ser. No. 11/317,204, filed Dec. 22, 2005, now issued U.S.Pat. No. 8,114,127, which is a continuation-in-part of U.S. patentapplication Ser. No. 10/873,987, filed Jun. 22, 2004, now issued U.S.Pat. No. 7,322,978, the disclosures of which are incorporated herein intheir entirety.

BACKGROUND OF THE INVENTION

1. The Field of the Invention

The present invention relates to soft tissue repair surgery, such asrotator cuff repair surgery. More specifically, the present inventionrelates to a bone anchor used to attach soft tissue to bone using asuture.

2. Related Technology

Soft tissue injuries, especially rotator cuff injuries, can occur fromrepeated stress or acute trauma. The rotator cuff is a group of musclesand tendons in the shoulder that attach to the humerus bone of the arm.The rotator cuff allows a person to rotate the arm and raise it abovethe head. A common injury to the rotator cuff occurs when repeatedstress or acute trauma causes the rotator cuff to partially or completetear away from the humerus bone. These and similar types of injuries mayrequire surgery to correctly reattach the soft tissue to the bone.

Various devices have been used to reattach soft tissue to bone. Knownmethods include staples, wedges, plugs, screws, and sutures alone.Threaded suture anchors, such as bone screws, have recently beendeveloped to provide a particularly firm location where a suture can beanchored to bone. In these systems, a suture is tied between the boneanchor and soft tissue. Providing a firm attachment point for the sutureis important because of the relatively strong forces that areexperienced in a flexing muscle.

Despite recent advances in bone anchors, existing bone anchors androtator cuff repairs can fail and have other disadvantages. Typically, arotator cuff repair fails either because the bone anchor dislodges orthe suture tears through the soft tissue. As force is applied to thesuture, the suture can cut through the soft tissue like a cheese wire,leaving the rotator cuff detached from the humerus bone. When one suturefails, it can place more stress on the surrounding sutures, thusincreasing the likelihood that other sutures will fail in like manner.

Using a greater number of sutures per unit area of soft tissue canminimize suture attachment failure. However, the number of sutures islimited by the space available for inserting bone anchors.Alternatively, additional sutures can be connected to a single boneanchor. Double and triple loading of bone anchors, however, increasesthe forces applied to the bone anchor and increases the likelihood thatthe bone anchor will fail by being pulled out of the bone into which itis secured.

Bone anchors can fail for various reasons. One reason is that existingbone anchors are not threaded to the proximal end of the anchor wherethe anchor meets the surface of the bone in the hard cortical boneregion. In existing bone screws, the proximal end is not threadedbecause the driver tool used to insert the bone anchor fits over a hexshaped protrusion. The hex protrusion cannot extend above the bonesurface so the screw is driven into the bone until the protrusion isbelow the surface. Since the protrusion has no threads, the bone anchordoes not engage the bone near the surface, but only the soft cancellousbone beneath the cortical bone layer. This feature of existing boneanchors is very problematic because it prevents a practitioner fromplacing the threads of the bone anchor in the harder cortical bone,which is near the bone surface.

Some existing anchors engage the sutures above the anchor threads. Suchscrews have an eyelet formed in the protrusion used to drive the screw.Sutures are looped in the eyelet and fed through the driver tool.Because the attachment point for the sutures is above the threads, thethreaded portion of the bone anchor experiences a high torque momentwhen a force is applied by the suture to the attachment point.Consequently, existing bone anchors are prone to experience a certaindegree of movement within the soft bone layer. In some cases, the boneanchor can retreat from the bone and rub against soft tissues overlayingthe bone anchor. This may result in the irritation or damage of suchtissues.

Recently, bone screws have been used that place the attachment point forthe sutures within the body of the screw, specifically within the boreof the screw. In these screws an attachment site within the bore iscreated using a small piece of suture. The ends of the suture are fedthrough holes near the proximal end of the screw to form a small sutureloop within the bore. Knots are tied in the end of the suture to preventthe ends from passing back though the holes. The suture loop within thebore provides an anchoring point for threading sutures used to securetissue in a surgical procedure.

One problem with these screws is that the knots that hold the sutureloop can come untied and/or break, which releases the sutures anchoredto the suture loop. This problem is particularly difficult to fix oncethe screw has been placed in a patient because it would require thesurgeon to remove the screw from the patient. An additional problem withusing suture loops as an attachment mechanism is that the suturematerial can fray as the anchored sutures slide on it. Furthermore, whenloading multiple sutures on the suture loop, the suture loop can flexand cause the sutures to bunch together. When a practitioner is using asuture the practitioner needs the suture to freely slide in the boneanchor. The friction and/or pinching that a suture loop can causebetween lengths of suture can cause suture capture, which isundesirable.

Therefore, what is needed is a bone anchor that better engages itssurrounding bone tissue and allows greater forces to be applied to thebone anchor without becoming dislodged or failing. In addition, a boneanchor is needed that can reduce suture capture.

BRIEF SUMMARY OF THE INVENTION

The bone anchors of the present invention overcome the disadvantages ofthe prior art discussed above by providing improved suture attachmentsites and improved threads for engaging bone tissue. In an exemplaryembodiment, the bone anchor of the present invention has an anchor bodyextending between a proximal end and a distal end. A continuous threadextends around the anchor body and is configured to engage both corticaland cancellous bone tissue. The anchor body includes an interior surfacethat defines a bore that opens at the proximal end of the anchor body.One or more transverse pins are placed in and across the bore interiorto provide one or more locations within the interior of the anchor bodyfor looping one or more sutures.

According to one embodiment, the pins are placed deep within the bore ofthe anchor body. This feature allows room for a socket to be formed inthe proximal end of the anchor body where a driver tool can be insertedfor driving the bone anchor into a bone. Because the driver tool isplaced on the interior of the bone anchor, the anchor body can bethreaded to the proximal end. Threading the proximal end of the anchorbody provides the bone anchor with the ability to better engage thecortical bone near the surface of the bone.

The placement of the pins also provides a more central location foranchoring sutures. The more centrally anchored sutures exert a force onthe anchor body that is more evenly distributed and more aligned withthe axis of the bone anchor. Consequently, the bone anchor can betterdistribute the exerted force to the surrounding bone tissue withoutcausing the bone tissue to weaken so as to cause loosening or withdrawalof the bone anchor.

The pins disposed within the bore of the anchor body also provide abetter attachment mechanism for attaching a suture than exists in theprior art. The pins are securely fixed to the anchor body. Unlike thebone anchors in the prior art, the bone anchors of the present inventiondo not rely on knots to secure sutures within the bore. In addition, thepins are made of a material that does not fray and is less likely tobreak.

Double and triple loading of the bone anchor with more than one sutureis more easily accomplished with a pin because the pins provideindividual attachment locations for each additional suture. In oneexemplary embodiment, two pins are disposed in the bore at right anglesto each other. Two sutures are loaded on the lower pin with the upperpin separating the two sutures. In another embodiment, the upper pin isalso loaded with a suture. This latter configuration properly spacesthree sutures and minimizes friction and suture capture among the threesutures.

In an exemplary embodiment, the anchor body has a non-threaded portionat the distal end that forms a stabilizing extension. The extensionprovides additional stability to the bone anchor by reducing thetendency of the anchor body to move or rotate laterally. Bone anchorsare often placed in a bone at an angle. Much like a longer tent stake isless likely to give out, the extension of the bone anchor of the presentinvention helps prevent the bone anchor from becoming dislodged.Stabilizing the bone anchor reduces the likelihood that the bone anchorwill fail and allows the bone anchor to be safely loaded with moresutures.

In yet another embodiment, the anchor body is a screw that includes aportion of fine threads and a portion of coarse threads. The finethreads are configured to engage hard bone tissue, such as corticalbone, and the coarse threads are configured to engage soft bone tissue,such as cancellous bone. A portion of the threads are made finer byincreasing the root diameter and increasing the surface angle of thethread. The pitch of the coarse threads and fine threads is kept thesame such that the proximal threads can follow the impression created bythe distal threads as the bone anchor is driven into a bone.

Optimizing the thread pattern for engaging different types of bonetissue allows the bone anchor to better engage adjacent bone tissue.Because the bone anchor can better engage adjacent bone tissue, the boneanchor can be loaded with additional sutures without compromisingstability of the bone anchor. The additional sutures per anchor reducethe stress placed on each individual suture through the soft tissue,which helps prevent the sutures from cutting through the soft tissue.

These and other objects and features of the present invention willbecome more fully apparent from the following description and appendedclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

To further clarify the above and other advantages and features of thepresent invention, a more particular description of the invention willbe rendered by reference to specific embodiments thereof which areillustrated in the appended drawings. It is appreciated that thesedrawings depict only typical embodiments of the invention and aretherefore not to be considered limiting of its scope. The invention willbe described and explained with additional specificity and detailthrough the use of the accompanying drawings in which:

FIG. 1 is a perspective view of an exemplary bone anchor according tothe invention;

FIG. 2 is a cross-sectional view of the bone anchor of FIG. 1 showing abore extending through the anchor body;

FIG. 3 is a proximal end view of the bone anchor of FIG. 1 showing adrive socket and two perpendicularly-arranged pins within the bore;

FIG. 4 is a cross-sectional view of the bone anchor of FIG. 1 with threesutures being looped around the two pins disposed in the bore;

FIG. 5A illustrates an alternative embodiment of an exemplary boneanchor of the invention having finer proximal threads for engaging hardcortical bone and coarser distal threads for engaging soft cancellousbone;

FIG. 5B illustrates the bone anchor of FIG. 5A with double flute threadon the cortical portion of the bone anchor;

FIG. 6 illustrates the bone anchor of FIG. 5A placed within a bone suchthat the fine threads engage a hard cortical bone region and coarsethreads engage a soft cancellous bone region; and

FIG. 6B illustrates the bone anchor of FIG. 6A

FIG. 7 illustrates an exemplary bone anchor of the invention placed in ahumerus bone of a person with sutures attached to the bone anchoringbeing looped through and securing the person's rotator cuff.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

With reference to FIG. 1, exemplary embodiments of the present inventionare directed to an improved bone anchor 10 for affixing soft tissue tobone, such as in a rotator cuff repair surgery. Bone anchor 10 has ananchor body 12, which extends between a proximal end 14 and a distal end16. Distal end 16 of anchor body 12 has a non-threaded portion thatforms a stabilizing extension 18. Stabilizing extension 18 helps preventlateral movement of anchor body 12 within bone tissue during use. Anchorbody 12 further comprises a threaded portion, which includes threads 20for engaging bone tissue.

Proximal end 14 includes an opening 30, which provides access to ahollow interior bore 30 of anchor body 12. A hex socket 22 is formed inbore 30 of anchor body 12, which allows bone anchor 10 to be driven intoa bone using a hex driver. It will be appreciated that bore 30 of anchorbody 12 can have any other desired shape, such as triangular, square,pentagonal, star-shaped, oval, etc. Transverse pins 23 a and 23 b aredisposed through anchor body 12 and provide attachment points forlooping sutures thereon.

FIG. 2 illustrates a cross-sectional view of bone anchor 10. In anexemplary embodiment, anchor body 12 has a length of about 8 to about 15mm a major diameter 26 of about 5 mm, and a root diameter 24 of about3.5 mm. Anchor body 12 can have sizes other than these; however, thesize of anchor body 12 is limited by the size of the bone where the boneanchor 10 is to be placed. For example, in rotator cuff repair surgery,increasing the diameter of anchor body 12 can reduce the number of boneanchors 10 that can be positioned at the repair site.

Bone anchor 10 has threads 20 that wrap continuously around anchor body12 in a desired (e.g., clockwise) direction. The pattern of threads 20determines in part how bone anchor 10 engages surrounding bone tissue.In one embodiment, threads 20 make about six turns around anchor body 12and extend toward proximal end 16.

As shown in FIG. 2, major diameter 26 and root diameter 24 may taperslightly inward toward distal end 16. The slight taper causes thethreads 20 to engage bone tissue more tightly as the bone anchor 10 isdriven further into a bone. Of course, bone anchor 10 can have threadsthat taper more or less depending on a practitioner's preference and/orthe needs of a patient.

Anchor body 12 also has a non-threaded portion at distal end 16, whichforms stabilizing extension 18. Stabilizing extension 18 is generallycylindrical and typically has a width less than root diameter 24. In oneembodiment, the length of extension 18 is more than about 20% of thelength of the threaded portion of anchor body 10. In another embodiment,extension 18 is more than 100% the length of the threaded portion and inyet another embodiment, more than about 200% of the length of thethreaded portion.

In one embodiment, extension 18 is configured to be inserted into apilot hole drilled into the bone where bone anchor 10 is to be placed.Preparing a pilot hole reduces the risk that insertion of the screw in abone will cause damage to bone anchor 10 and/or fracture bone tissue asthe bone anchor 10 is inserted into the bone. Preventing damage to boneanchor 10 and surrounding bone tissue reduces the chances that boneanchor 10 will become loosened or fail during use. In anotherembodiment, the bone anchor can have a self drilling distal end.

Anchor body 12 is advantageously made from a strong biocompatiblematerial, such as a titanium alloy or stainless steel. Alternatively,anchor body 12 can be made from a biodegradable material, such aspoly-l-lactic acid (PLLA) that can be absorbed into adjacent bone tissueover time as the repair site heals. Other biocompatible and/orbiodegradable materials suitable for use in bone anchors are known tothose skilled in the art.

Bore 30 opens at proximal end 14 to provide access to the interior ofanchor body 12. In an exemplary embodiment, a proximal portion of bore30 is hexagonally shaped to form a hex socket 22 for receiving a hexdriver. This female type driver tool engagement mechanism eliminates theneed to have a protruding proximal end 16. Instead, proximal end 16 issubstantially flat and can be placed at or just below a bone surface, asdiscussed more fully below.

As shown in FIGS. 2 and 3, hex socket 22 can be wider than the distalportion of bore 30. For example, a ridge 34 can be formed at the distalend of hex socket 22. Ridge 34 acts as a stop to limit how deep a hexdriver can be inserted therein (e.g., to protect post 23 b and/or asuture attached thereto). Alternatively, the insertion depth of a hexdriver can be controlled by placing a ridge of material on the hexdriver. In this case, insertion of the driver would be stopped when theridge on the driver engages the proximal end 16 of the anchor body 12.

The distal portion of bore 30 also contains one or more transverse pinsfor looping sutures thereon. Pins 23 a and 23 b are formed or insertedin anchor body 12 lying across bore 30. The diameter of pins 23 a and 23b are selected such that there is sufficient space between pin 23 a andpin 23 b and interior surface 28 for passing a suture around the pins 23a and 23 b. In addition to providing a location for looping sutures,pins 23 a and 23 b provide additional structural support (i.e., anendoskeleton) to anchor body 12.

Pins 23 a and 23 b are disposed in bore 30 substantially non-parallel toeach other. As illustrated in FIG. 3, in one embodiment, pins 23 a and23 b are at right angles to each other. Offsetting pins 23 a and 23 bexposes portions of pin 23 a that would otherwise be occluded from thetop by pin 23 b. Such a configuration allows a suture to be loaded onpin 23 a on either side of pin 23 b, as shown in FIG. 4.

Bone anchor 10, in FIG. 4, is illustrated loaded with three sutures 36a, 36 b, and 36 c (collectively sutures 36). Pin 23 a is shown loadedwith sutures 36 a and 36 b extending on either side of pin 23 b. Pin 23b has a single suture 36 c loaded thereon. Each suture has its own spaceto slide on its respective pin 23 a or 23 b. The proper spacing ofsutures 36 in bone anchor 10 prevents sutures 36 from rubbingextensively or getting caught on one another.

Another advantageous feature of pins 23 a and 23 b is their positiondistal to hex socket 22 and within bore 30. Pins 23 a and 23 b areplaced within bore 30 such that the forces applied by sutures 36 aretransferred to a more central location within anchor body 12. Forcesapplied to bone anchor 10 below the surface of a bone are less likely tocause bone anchor 10 to become loosened or dislodged. Pins 23 a and 23 bare placed below hex socket 22 so a hex driver can be inserted withouthitting the pins. This placement also allows sutures to be threadedthrough a hole in a driver tool (not shown) so that bone anchor 10 canbe installed pre-loaded with sutures.

While bone anchor 10 has been illustrated with two pins (i.e., pins 23 aand 23 b), bone anchor 10 may have more or fewer pins depending on therequired number of sutures and/or the space available within bore 30 forplacing more sutures. For instance, in another embodiment, the anchorbody 12 may have a single post with one or more sutures loaded thereon.Furthermore, a second pin can be disposed in bore 30 even where suturesare to be placed only on one pin, with the second pin being used solelyto separate sutures. In addition, a second pin can be placed in anchorbody 12 for structural support only.

Pins 23 a and 23 b are made from a strong metal or synthetic fiber so asto provide a rigid attachment point for sutures 36. In an exemplaryembodiment, pins 23 a and 23 b are cylindrical to provide a smoothsurface for sutures 36 to slide against. While pins 23 a and 23 b areillustrated as straight, pins 23 a and 23 b can be bent or have shapesother than cylindrical. Straight pins, however, can be more easilyplaced in anchor body 12 and therefore can reduce the cost andcomplexity of manufacturing bone anchor 10. The foregoing and similarattachment devices are examples of rigid attachment means for attachinga suture to an anchor.

In one embodiment, one or both of pins 23 a and 23 b are made from aradioopaque material such as titanium or stainless steel. A radioopaquepin can be used with a radiotransparent anchor body, such as an anchorbody made from a biodegradable material such as PLLA. This configurationof materials allows a practitioner to identify and locate bone anchor 10in a radiograph when bone anchor 10 is made mostly of biodegradablematerials.

The bone anchor according to the present invention need not be formed asa threaded device, but can also be formed as a tap-in type anchor. Also,the measurements, angles and ratios between the dimensions of the boneanchor can be varied from those described above and in the followingalternative embodiment so as to be suitable for the conditions andapplications in which the bone anchor is to be used.

FIG. 5A shows an alternative embodiment of the bone anchor of thepresent invention having a section of finer threads 38 at the proximalend 16 and a section of coarser threads 40 distal thereto. Fine threads38 and coarse threads 40 have the same major diameter 42 which has aslight taper illustrated by lines 44 a and 44 b. Fine thread 38 andcoarse threads 40, have different root diameters 46 and 48 respectively.Root diameters 46 and 48 have a slight taper similar to major diameterthe taper shown by lines 44 a and 44 b.

Fine threads 38 are finer because they have a wider root diameter 46.Root diameter 46 of fine thread 38 is wider than root diameter 48 ofcoarse threads even after subtracting out the increase in width due tothe overall taper of anchor body 12 as illustrated by lines 44 a and 44b. Fine threads 38 have root diameter 46 and a major diameter 42 thatare configured to engage harder bone. Coarse threads 40 have a rootdiameter 48 and major diameter 42 that are configured to engage softbone. In an exemplary embodiment, major diameter 42 is about 5.3 mm,root diameter 46 is about 4.8 mm and root diameter 48 is about 3.3 mm.Fine threads 38 can have a similar shape as coarse threads 40 or adifferent shape as desired. For example, fine threads 38 can have alarger or smaller thread angle.

In one embodiment, fine threads 38 have the same pitch as coarse threads40. By keeping the pitch the same between thread sections, the finerthreads 38 will be able to use the same impression cut by coarse threads40.

FIG. 5B shows yet another alternative embodiment of the presentinvention where fine threads 38 form a double flute. A first flute 39 afollows the thread pattern of coarse threads 40 such that first flute 39a follows the grooves created by coarse threads 40 as the bone anchor 10is driven into a bone. In an exemplary embodiment, second flute 39 b hasthe same pitch as first flute 39 a. Second flute 39 b can have a similarshape as flute 39 a or a different shape as desired. For example,threads 39 b can have a larger or smaller thread angle and/or majordiameter.

FIG. 6 shows bone anchor 10 disposed in a typical bone 50 having acortical bone region 52 and a cancellous bone region 54. Cortical boneregion 52 comprises dense bone, while cancellous bone region 54comprises bone that is soft or spongy. When bone anchor 10 is properlyinserted into bone 50, fine threads 38 engage the hard cortical boneregion 52 and coarse threads 40 engage the softer cancellous bone region54.

In manufacturing bone anchor 10, in accordance with the presentinvention, anchor body 12 and posts 23 can be cast and formed in a die.Alternatively anchor body 12 can be cast or formed and posts 23 a and 23b inserted later. For instance, anchor body 12 can be cast and formedfrom PLLA. Anchor body 12 can then be drilled to prepare holes forstainless steel pins 23 a and 23 b.

The suture anchors according to the present invent can be distributed topractitioners with one or more of sutures 36 threaded through bore 30and looped to pins 23 a and/or 23 b. In one method of manufacturing boneanchor 10, sutures 36 are looped on pins 23 a and 23 b as pins 23 a and23 b are inserted into anchor body 12.

An example of a type of suture suitable for use in conjunction with thebone anchor of the present invention is #2 braided polyester. If morethan one strand of sutures 36 is used, the sutures can be a differentcolor such that a practitioner can more easily pair the ends of thesutures during a surgical operation.

FIG. 7 illustrates the use of bone anchor 10 in a rotator cuff repairsurgery. Bone anchor 10 is placed in humerus bone 54, and sutures 36 arepassed through rotator cuff 56 and tied. Before bone anchor 10 isinserted in humerus bone 54 a pilot hole may be drilled. Bone anchor 10is inserted into the pilot hole using a driver tool until proximal end14 is substantially flush with the outer surface of humerus bone 54.Bone anchor 10 is advantageously placed in humerus bone 54 at an angleto the tangent of the humerus bone, also known as the “dead man'sangle.”

Because bone anchor 10 is placed in humerus bone 54 at an angle,extension 18 provides a mechanical advantage against bone anchor 10moving laterally and opening the angle to the tangent. By preventinglateral movement, extension 18 prevents sutures 36 from loosening oncesutures 36 have been properly tied. In addition, if bone anchor 10 wereto move within bone 54, bone anchor 10 can become dislodged and fail.Extension 18 does not have threads thereon, which reduce friction asbone anchor 10 is driven into a pilot hole.

Proximal end 14 of bone anchor 10 is substantially flat ornon-protruding such that bone anchor 10 can be placed at or just belowthe surface of bone 54. Threads extend to proximal end 14 such that boneanchor 10 has maximum engagement with bone 54. The opening at proximalend 14 also allows for sutures 36 to exit the bore. The opening of thebore is smooth such that sutures 36 can easily slide thereon.

Sutures 36 exit bone anchor 10 at proximal end 14 and are drawn throughthe soft tissue of rotator cuff 56. Sutures 36 can be spaced to moreevenly distribute the load exerted by rotator cuff 56. As shown in FIGS.5 and 7, sutures 36 exert a force on bone anchor 10 on the pins in thebone and at proximal end 14. Because proximal end 14 is at or below thesurface of bone 54, less torsion is applied to bone anchor 10. Instead,the force of rotator cuff 56 is distributed vertically along the anchorbody through the pins. Consequently, bone anchor 10 is less likely to bedislodged and fail.

The present invention may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. The describedembodiments are to be considered in all respects only as illustrativeand not restrictive. The scope of the invention is, therefore, indicatedby the appended claims rather than by the foregoing description. Allchanges which come within the meaning and range of equivalency of theclaims are to be embraced within their scope.

1. A suture anchor assembly comprising: an anchor body having an axisand a hollow interior bore extending from an opening at a proximal endof the anchor body through a portion of the anchor body, wherein aproximal portion of the interior bore includes a socket for receivingtherein a driver, the socket having a polygonal shape; a rigidtransverse pin positioned within and across the interior bore of theanchor body that provides a rigid attachment point for sutures; and atleast one tissue securing suture looped around the transverse pin andhaving ends.
 2. The suture anchor assembly according to claim 1, whereinthe anchor body is made of titanium alloy or stainless steel.
 3. Thesuture anchor assembly according to claim 1, wherein the pin comprisestitanium alloy or stainless steel.
 4. The suture anchor assemblyaccording to claim 1, wherein the anchor body is tapered.
 5. The sutureanchor assembly according to claim 1, wherein the anchor body comprisesthreads on an outer surface of the anchor body, wherein the threadsextend to the proximal end of the anchor body.
 6. The suture anchorassembly according to claim 1, wherein the anchor body has a selfdrilling distal end.
 7. The suture anchor assembly according to claim 1,wherein the pin is straight.
 8. The suture anchor assembly as recited inclaim 1, wherein the interior bore includes a proximal portion and adistal portion, wherein the proximal portion of the interior boreincludes a socket for receiving a driver, and wherein the pin isdisposed in the distal portion of the interior bore.
 9. The sutureanchor assembly according to claim 8, wherein the proximal portion has ahexagonally shaped socket and the distal portion is cylindrical, whereinthe one or more sutures are looped around the pin in the distal portionof the interior bore.
 10. The suture anchor assembly as recited in claim1, wherein the interior bore has a shape for receiving a driver fordriving the suture anchor into a bone.
 11. The suture anchor assemblyaccording to claim 1, wherein the socket includes planar surfaces whichare parallel to the axis of the anchor body.
 12. A suture anchorassembly for attachment of tissue to bone, the suture anchor assemblycomprising: an anchor body having a distal end, a proximal end, an axis,an outer surface and an interior bore, the interior bore beginning atthe proximal end and extending partially through the anchor body; arigid pin disposed in the interior bore, wherein the rigid pin ispositioned across the axis of the anchor body; and at least one tissuesecuring suture looped around the rigid pin and having ends.
 13. Thesuture anchor assembly according to claim 12, wherein the anchor bodycomprises threads on the outer surface of the anchor body, wherein thethreads extend to the proximal end of the anchor body.
 14. The sutureanchor assembly according to claim 12, wherein the interior bore has ashape so as to accommodate a driver head for driving the anchor body,and the interior bore includes a plurality of surfaces for contactingthe driver head, the plurality of surfaces including first and secondplanar faces that intersect along the axis of the anchor body.
 15. Thesuture anchor assembly according to claim 14, wherein the interior boreincludes a proximal portion and a distal portion, wherein the proximalportion includes the first and second planar faces for contacting thedriver head, and wherein the rigid pin is disposed in the distalportion.
 16. The suture anchor assembly according to claim 15, whereinthe proximal portion is hexagonal and the distal portion is cylindrical,wherein the one or more sutures are looped around the pin in the distalportion of the interior bore.
 17. The suture anchor assembly as recitedin claim 12, wherein the pin is transverse to the anchor body.
 18. Thesuture anchor assembly as recited in claim 17, wherein the axis of therigid pin is generally perpendicular to the axis of the anchor body. 19.The suture anchor assembly as recited in claim 12, wherein the one ormore tissue securing sutures have free ends.
 20. The suture anchorassembly as recited in claim 12, wherein the one or more tissue securingsutures extend outside the anchor body.
 21. The suture anchor assemblyas recited in claim 20, wherein the one or more tissue securing suturesexit through an opening at the proximal end of the anchor body.
 22. Thesuture anchor assembly as recited in claim 21, further including adriver tool positionable in the proximal portion of the interior bore,wherein the one or more sutures are threaded through a hole in thedriver tool.
 23. The suture anchor assembly as recited in claim 12,wherein the one or more tissue securing sutures have free ends.
 24. Thesuture anchor assembly as recited in claim 12, wherein a tissue securingsuture has a first loose end and a second loose end.
 25. The sutureanchor assembly as recited in claim 12, wherein the one or more tissuesecuring sutures are slidably looped around the rigid pin.
 26. Thesuture anchor assembly according to claim 12, wherein the rigid pin isstraight.
 27. A suture anchor assembly comprising: an anchor body havingan axis and an interior bore extending from an opening at a proximal endof the anchor body through a portion of the anchor body, wherein aportion of the interior bore has a polygonal shape defined by at least afirst planar face and a second planar face, the at least first planarface and the second planar face intersecting along the axis of theanchor body, wherein the interior bore includes a proximal portion and adistal portion; a rigid pin disposed in the distal portion of theinterior bore and being positioned transversely relative to the axis ofthe anchor body; at least one tissue securing suture looped around therigid pin, wherein the at least one tissue securing suture has a firstend and a second end; and a driver tool including a driver head, whereinthe driver head is receivable inside the proximal portion of theinterior bore of the anchor body to drive the anchor body, wherein theinterior bore has the polygonal shape to accommodate the driver head fordriving the suture anchor.
 28. The suture anchor assembly according toclaim 27, wherein the at least first planar face and second planar faceare disposed generally parallel to the axis of the anchor body.
 29. Thesuture anchor assembly according to claim 27, wherein the proximalportion is hexagonal and the distal portion is cylindrical, wherein theat least one tissue securing suture is looped around and contacts therigid pin in the distal portion of the interior bore.
 30. The sutureanchor assembly according to claim 27, wherein the rigid pin isstraight.
 31. The suture anchor assembly according to claim 27, whereinthe anchor body comprises threads on an outer surface of the anchor bodyand that extend to the proximal end of the anchor body.
 32. A sutureanchor assembly comprising: an anchor body having a longitudinal axisand a central bore extending from an opening at a proximal end of theanchor body through a portion of a length thereof, wherein a portion ofthe central bore includes at least a first planar face and a secondplanar face, the at least first planar face and second planar faceintersecting along the longitudinal axis of the anchor body; a rigidmember having a longitudinal axis and disposed in the central bore,wherein the longitudinal axis of the rigid member extends across thelongitudinal axis of the anchor body; and at least one tissue securingsuture looped around the rigid member, wherein the at least one tissuesecuring suture has a first end and a second end.
 33. The suture anchorassembly according to claim 32, wherein the anchor body is metal. 34.The suture anchor assembly according to claim 32, wherein the rigid pinis metal.
 35. The suture anchor assembly according to claim 32, whereinthe anchor body is tapered.
 36. The suture anchor assembly according toclaim 32, wherein the anchor body comprises threads on an outer surfaceof the anchor body, wherein the threads extend to the proximal end ofthe anchor body.
 37. The suture anchor assembly according to claim 32,wherein the anchor body is self-tapping.
 38. The suture anchor assemblyaccording to claim 32, wherein the rigid member is straight.
 39. Thesuture anchor assembly as recited in claim 32, wherein the central boreincludes a first section and a second section, and the first sectionaccommodates a driver head and the rigid member is disposed in thesecond section.
 40. The suture anchor assembly according to claim 39,wherein the first section has a hexagonally shaped cross section, thesecond section is cylindrical, and the at least one tissue securingsuture is looped around and contacts the rigid member in the secondsection of the central bore.
 41. The suture anchor assembly as recitedin claim 32, wherein the central bore has a cross-sectional shape so asto accommodate a driver head for driving the suture anchor.
 42. Thesuture anchor assembly according to claim 32, wherein the at least firstplanar face and second planar face are generally parallel to thelongitudinal axis of the anchor body.
 43. A suture anchor assembly forattachment of tissue to bone, the suture anchor assembly comprising: ananchor body having including a distal end, a proximal end, alongitudinal axis, an outer surface and a central bore, the central borebeing located at the proximal end and extending partially through theanchor body; a rigid member having a longitudinal axis and disposed inthe central bore, wherein the longitudinal axis of the rigid memberextends across the longitudinal axis of the anchor body; and at leastone tissue securing suture looped around the rigid member including afirst end and a second end.
 44. The suture anchor assembly according toclaim 43, wherein the anchor body comprises a plurality of threadsextending from the outer surface of the anchor body, and the pluralityof threads extend to the proximal end of the anchor body.
 45. The sutureanchor assembly according to claim 43, wherein the central bore has across-sectional shape so as to accommodate a driver head for driving theanchor body, and the central bore includes a plurality of contactsurfaces for the driver head, the plurality of contact surfacesincluding a first planar face and a second planar face, wherein thefirst planar face and the second planar face intersect along thelongitudinal axis of the anchor body.
 46. The suture anchor assemblyaccording to claim 45, wherein the central bore includes a first sectionand a second section, the first section includes the first planar faceand the second planar face that accommodates the driver head, and therigid member is disposed in the second section.
 47. The suture anchorassembly according to claim 46, wherein the first section has ahexagonally shaped cross section and the second section is cylindrical,and the at least one tissue securing suture is looped around andcontacts the rigid member in the second section of the central bore. 48.The suture anchor assembly as recited in claim 43, wherein thelongitudinal axis of the rigid member is transverse to the longitudinalaxis of the anchor body.
 49. The suture anchor assembly as recited inclaim 48, wherein the longitudinal axis of the rigid member is generallyperpendicular to the longitudinal axis of the anchor body.
 50. Thesuture anchor assembly as recited in claim 43, wherein the first end ofthe at least one tissue securing suture is unattached to the second endof the at least one tissue securing suture.
 51. The suture anchorassembly as recited in claim 43, wherein the first end and the secondend of the at least one tissue securing suture extend out of the anchorbody.
 52. The suture anchor assembly as recited in claim 51, wherein thefirst end and the second end of the at least one tissue securing sutureextend out of an opening at the proximal end of the anchor body.
 53. Thesuture anchor assembly as recited in claim 52, including a driver havinga cannula received in a portion of the central bore, the cannula havinga distal opening and a proximal opening, wherein the first end and thesecond end of the at least one tissue securing suture extend out of theproximal opening of the cannula.
 54. The suture anchor assembly asrecited in claim 43, wherein the first end of the at least one tissuesecuring suture is free to move relative to the second end of the atleast one tissue securing suture.
 55. The suture anchor assembly asrecited in claim 43, wherein the first end is a first loose end of theat least one tissue securing suture and the second end is a second looseend of the at least one tissue securing suture.
 56. The suture anchorassembly as recited in claim 43, wherein the at least one tissuesecuring suture is slidably releasable from the rigid member.
 57. Thesuture anchor assembly according to claim 43, wherein the rigid memberis straight.
 58. A suture anchor assembly comprising: an anchor bodyhaving a longitudinal axis and a central bore extending from an openingat a proximal end of the anchor body through a portion of a lengththereof, wherein a portion of the central bore has a cross-sectionalshape, and the central bore includes at least a first planar face and asecond planar face, the at least first planar face and second planarface intersecting along the longitudinal axis of the anchor body, andthe central bore includes a first section and a second section; a rigidmember having a longitudinal axis and disposed in the central bore,wherein the longitudinal axis of the rigid member extends across thelongitudinal axis of the anchor body, and the rigid member is disposedin the second section; at least one tissue securing suture looped aroundthe rigid member, wherein the at least one tissue securing suture has afirst end and a second end; and a driver including a driver head,wherein the driver head is receivable inside the central bore in thefirst section of the anchor body to drive the anchor body, and thecentral bore has the cross-sectional shape to accommodate the driverhead for driving the suture anchor.
 59. The suture anchor assemblyaccording to claim 58, wherein the at least first planar face and secondplanar face are disposed generally parallel to the longitudinal axis ofthe anchor body.
 60. The suture anchor assembly according to claim 58,wherein the first section has a hexagonally shaped cross section, thesecond section is cylindrical, and the at least one tissue securingsuture is looped around and contacts the rigid member in the secondsection of the central bore.
 61. The suture anchor assembly according toclaim 58, wherein the rigid member is straight.
 62. The suture anchorassembly according to claim 58, wherein the anchor body comprises aplurality of threads extending from an outer surface of the anchor body,and the plurality of threads extend to the proximal end of the anchorbody.